Answer:
B
Explanation:
The moon moves in the earth's shadow and is blocked by the earth .
Answer:
Explanation:
Pollen tubes are produced by the male gametophytes of seed plants. Pollen tubes act as conduits to transport the male gamete cells from the pollen grain—either from the stigma (in flowering plants) to the ovules at the base of the pistil or directly through ovule tissue in some gymnosperms.
Answer:
20 million years
Explanation:
If we have a neutral mutation rate of one mutation per 5 million years, then the total of eight mutation between the two different species would be 20 million years. This is because both species will have 4 mutations in those 20 million years, so combined, both by 4, will have 8 mutations between them. So few mutations on so much time will result in two species that are very similar to each other even after 20 million years of evolution, even making them hardly distinguishable, especially if it comes to defining fossil records from them both. A nice example of this are the members of the felidae (cat) family, which are all very closely related, and are almost identical, thus making it extremely hard to distinguish two species of the same or similar size by their fossils.
